diff options
| author | Andrii Nakryiko <andrii@kernel.org> | 2023-12-13 11:08:35 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2023-12-13 15:47:05 -0800 |
| commit | 29c302a2e265a356434b005155990a9e766db75d (patch) | |
| tree | e40449d783e85ca73b620a87592a13ab9b7bd0c4 /tools/lib/bpf/libbpf.c | |
| parent | c6c5be3eee975ae640966844db66d404c1de79b1 (diff) | |
libbpf: further decouple feature checking logic from bpf_object
Add feat_supported() helper that accepts feature cache instead of
bpf_object. This allows low-level code in bpf.c to not know or care
about higher-level concept of bpf_object, yet it will be able to utilize
custom feature checking in cases where BPF token might influence the
outcome.
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231213190842.3844987-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/lib/bpf/libbpf.c')
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index d2828a26b011..2b7962120730 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -5074,17 +5074,14 @@ static struct kern_feature_desc { }, }; -bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id) +bool feat_supported(struct kern_feature_cache *cache, enum kern_feature_id feat_id) { struct kern_feature_desc *feat = &feature_probes[feat_id]; - struct kern_feature_cache *cache = &feature_cache; int ret; - if (obj && obj->gen_loader) - /* To generate loader program assume the latest kernel - * to avoid doing extra prog_load, map_create syscalls. - */ - return true; + /* assume global feature cache, unless custom one is provided */ + if (!cache) + cache = &feature_cache; if (READ_ONCE(cache->res[feat_id]) == FEAT_UNKNOWN) { ret = feat->probe(); @@ -5101,6 +5098,17 @@ bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id) return READ_ONCE(cache->res[feat_id]) == FEAT_SUPPORTED; } +bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id) +{ + if (obj && obj->gen_loader) + /* To generate loader program assume the latest kernel + * to avoid doing extra prog_load, map_create syscalls. + */ + return true; + + return feat_supported(NULL, feat_id); +} + static bool map_is_reuse_compat(const struct bpf_map *map, int map_fd) { struct bpf_map_info map_info; |